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Bacterial spot of tomatoes caused by four species of <i>Xanthomonas</i> can be a devastating disease resulting in plant defoliation and reduction of fruit quality and yield. The disease can be very difficult to manage because there are few effective registered treatments, tomatoes are often grown in regions where conditions favor infection, and copper-resistance is widespread in pathogen populations. Mature, fruit-bearing ‘Roma’ tomato plants (10 plants/3-m replication) were treated in the field with test materials using a mist-blower, air-dried, and then inoculated with a copper-sensitive strain of <i>X. vesicatoria</i> (10⁷ cfu/ml and 0.5 L/rep) using the same equipment. Plots were watered for 5 h on three consecutive days using overhead sprinklers. After 3 weeks, severity of bacterial spot was rated on 30 randomly collected leaves/rep. Mancozeb (1200 g/Ha) was least effective; whereas kasugamycin (100 mg/L), fixed copper (500 g Mce/Ha), quinoxyfen (93 g/Ha) and mixtures of copper-mancozeb and kasugamycin-mancozeb effectively and similarly reduced disease severity from that of the untreated control. Kasugamycin-quinoxyfen was the most effective in these trials reducing severity by an average of 80%. Use of kasugamycin or any product will depend on integration of resistance management strategies including tank mixtures of different products with different modes of action and their rotation when multiple applications are needed for managing the disease under favorable environments.<p><p>Keywords: Bacteria-Phytoplasma-Spiroplasma-Fastidious Prokaryote, Vegetables, Tomato